7of8Douglas Pesek describes the weather channel prompter to children Matthew Pesek, Nathan Pesek, and Justin Pesek at the end of their tour of the Trailblazer II, a traveling science museum for students, on Friday, June 14, 2013, in Houston. The Boeing Company and the Texas Alliance for Minorities in Engineering unveils the mobile museum trailer which has exhibits involving aerodynamics, space, exploration, energy, weather, and biotechnology. ( Mayra Beltran / Mayra Beltran )Photo: Mayra Beltran, Staff

8of8"There goes my hope of you becoming a doctor, maybe an engineer" says Stephen Percival while his son Stephen Percival Jr., has a skirmish reaction to a surgery video while touring the Trailblazer II, a traveling science museum for students, on Friday, June 14, 2013, in Houston. The Boeing Company and the Texas Alliance for Minorities in Engineering unveils the mobile museum trailer which has exhibits involving aerodynamics, space, exploration, energy, weather, and biotechnology. ( Mayra Beltran / Mayra Beltran )Photo: Mayra Beltran, Staff

For many years now, a giant science lab on wheels has been roaming the highways, byways and city streets in Texas.

The rolling science museum was designed to pique the interest of low-income and minority youngsters and encourage them to consider careers in science, technology, engineering and math - now often abbreviated as STEM.

This summer, the Texas Alliance for Minorities in Engineering is showcasing its second rolling lab, a 40-foot gooseneck trailer that soon will be pulling up in front of libraries, community centers and schools and inviting children in to examine the hands-on experiments with gravity, weather energy and other scientific wonders.

At the moment, however, Trailblazer II is making its way around to the major corporate donors that donated the money to get the behemoth on the road. On Friday morning, it was parked at Boeing near Ellington Airport and the children of employees as well as local VIPs came for tours.

Later this month the rig - which cost $250,000 to outfit - will visit Shell. Other big corporate contributors include Lockheed Martin, 3M and BASF.

"We go to a lot of small towns," said Savita Raj, executive director of the Texas Alliance for Minorities in Engineering. Each year, the traveling exhibit serves 10,000 to 15,000 students and covers about the same amount of miles.

Not all areas are served equally, in part because of the sheer size of Texas. On Friday, one donor offered to sponsor three visits to the Panhandle, Raj said.

A retired science teacher drives the trailer and gives the tour of the exhibit inside, said Raj, who added that she's looking for a "clone" to get behind the wheel of the pickup truck that will tow Trailblazer II across Texas. In the meantime, the group is booking visits.

Thirteen-year-old George Ducommun was the guest of his neighbor, Scott Van Dusen, who oversees fire protection and emergency management for Boeing in the Houston area.

Ducommun liked the mock up of the spaceship designed for a trip to Mars.

"It's not every day you get to see that," said Ducommun, who lives in Manvel and hopes to be a pilot.

One of the tour guides on hand Friday showed the three Pesek boys how to create a tornado by using two soda bottles connected together. The blue water inside swirled into a funnel-like cloud.

"Don't hit anybody with it," the guide said as 6-year-old Justin Pesek gave the bottles a shake. Justin, along with brothers Matthew, 11, and Nathan, 10, were visiting their father, Douglas Pesek, who works in systems engineering for Boeing's space launch system.

Matthew said he liked an experiment about gravity that uses soda cans while Nathan said the tornado experiment filled in some gaps in his knowledge of how big twisters form.

David Williams, a teacher who works with at-risk youth at Alvin Independent School District came at the suggestion of his sister who works with an engineering services firm.

Williams said he plans to talk to the lead science teacher about getting the trailer to visit schools in Alvin. Students are eager for hands-on activities, he said.

While the trailers are probably the most visible symbols of Texas Alliance for Minorities in Engineering, the group has a much larger outreach program. It gives out thousands of science-themed comic books, provides college scholarships to teens studying in technical subjects and sponsors math and science teams of students from grades 6-12.

Raj said the rocket science team in Presidio, one of the poorest school districts in Texas, has been a national finalist for several years in the Team America Rocketry Challenge and was part of the White House science fair last year.

President Barack Obama singled out the group of students for their hard work and dedication - which included raffling off a goat to raise money.

About 300 teens are participating in the teams statewide - about 30 in each of 10 regions - and 100 percent of them go on to college, Raj said. Eighty-three percent end up going into the sciences, including more than half opting for engineering.

L.M. Sixel writes about the economy and the workplace for the Houston Chronicle. She writes a weekly column called "Working" that appears each Thursday.

She started her newspaper career at the Beaumont Enterprise. Before that, she earned a Bachelor's degree in sociology from the University of Wisconsin-Madison and a Master's degree in economic history from the London School of Economics.